NSK
Report
- Report Number
- 9611253-2022-00061
- Event Type
- Malfunction
- Date Received
- August 31, 2022
- Date of Event
- July 14, 2022
- Report Date
- October 11, 2022
- Manufacturer
- NAKANISHI INC.
- Product Code
- EFB
- PMA / PMN Number
- K113655
- Product Problem
- Yes
- Report Source
- Manufacturer report
- Reporter Location
- ME, US
- Reporter Occupation
- 501
Narratives
THE SAME ADVERSE EVENT IN THIS REPORT HAS BEEN REPORTED TO THE FDA SEPARATELY BY THE DISTRIBUTOR, NSK AMERICA CORPORATION, UNDER REPORT NUMBER 1422375-2022-00033.
UPON RECEIVING THE DEVICE INVOLVED IN THE MDR EVENT FROM THE DISTRIBUTOR, NAKANISHI CONDUCTED A FAILURE ANALYSIS OF THE RETURNED DEVICE [REPORT NO. C220812-01]. THESE ACTIVITIES ARE DESCRIBED IN MORE DETAIL BELOW. METHODOLOGY USED: A) NAKANISHI EXAMINED THE DEVICE HISTORY RECORD AND THE REPAIR HISTORY FOR THE SUBJECT Z800L DEVICE [0BG30668]. THERE WERE NO PROBLEMS OBSERVED DURING MANUFACTURING OR TESTING NOTED IN THE DHR. THERE WERE ALSO NO REPAIR HISTORY RECORDS SINCE THE DEVICE WAS SHIPPED. B) NAKANISHI CONDUCTED A VISUAL INSPECTION OF THE RETURNED DEVICE AND OBSERVED THE FOLLOWING: - THE HEADCAP AND THE CARTRIDGE WERE SEPARATED FROM THE DEVICE. - THE BEARING OF THE CARTRIDGE REAR SIDE WAS DISASSEMBLED. - THERE WERE NO ABRASION OR DETERIORATION OF THE HEADCAP THREAD AND HEAD THREAD. C) NAKANISHI MOUNTED A NEW CARTRIDGE TO THE HEAD OF THE HANDPIECE AND CUT A MELAMINE PLATE WHILE ROTATING THE HANDPIECE UNDER NO LOAD AT THE MAXIMUM SPEED (440,000MIN-1) TO CHECK WHETHER OR NOT THE HEADCAP WOULD LOOSEN. THE REPORTED LOOSENING OF THE HEADCAP WAS NOT REPLICATED IN THE DEVICE EVALUATION. D) NAKANISHI TOOK PHOTOGRAPHS OF ALL THE DISASSEMBLED PARTS AND KEPT THEM IN THE INVESTIGATION REPORT NO. C220812-01. CONCLUSIONS REACHED BASED ON THE INVESTIGATION AND ANALYSIS RESULTS: A) ALTHOUGH NAKANISHI COULD NOT REPLICATE THE REPORTED EVENT, NAKANISHI CONSIDERS THE POSSIBILITY FROM SIMILAR EVENT THAT NSK HAS EXPERIENCED IN THE PAST, THE COMBINATION OF THE REDUCED HEADCAP TIGHTENING FORCE TOGETHER WITH ABNORMAL VIBRATION COULD RESULT IN THE REPORTED HEADCAP LOOSENING/SEPARATION. B) MISUSE BY THE USER LED TO THE ABOVE ISSUE, WHICH CONTRIBUTED TO THE REPORTED EVENT. C) IN ORDER TO PREVENT A RECURRENCE OF THE HEADCAP LOOSENING/SEPARATION, NAKANISHI TOOK THE FOLLOWING ACTIONS: C.1) NAKANISHI REVIEWED THE OPERATION MANUAL AND RECONFIRMED THE CLARITY AND UNDERSTANDABILITY OF THE INSTRUCTIONS. C.2) NAKANISHI WILL REPORT THE ABOVE EVALUATION RESULTS TO THE DISTRIBUTOR AND DIRECTED THE DISTRIBUTOR TO REMIND THE USER OF THE IMPORTANCE OF MAINTENANCE AS INSTRUCTED IN THE OPERATION MANUAL.
ON (B)(6) 2022, NAKANISHI BECAME AWARE OF A MALFUNCTION OF A NSK HANDPIECE THROUGH A COMPLAINT INPUT INTO THE COMPLAINT DATABASE BY A DISTRIBUTOR (NSK AMERICA). DETAILS ARE AS FOLLOWS: THE EVENT OCCURRED ON (B)(6) 2022. THE DENTIST WAS PERFORMING A DENTAL PROCEDURE ON A PATIENT USING THE Z800L HANDPIECE (SERIAL NO. (B)(4) DURING THE PROCEDURE, THE HEADCAP OF THE HANDPIECE CAME OFF, AND INTERNAL PARTS LANDED IN THE PATIENT'S MOUTH. THE PARTS WERE RECOVERED, AND THE PATIENT WAS NOT AFFECTED.
Devices
| Seq | Brand | Generic | Product Code | Manufacturer | Model | Lot | UDI-DI |
|---|---|---|---|---|---|---|---|
| 2806493 | NSK | HANDPIECE, AIR-POWERED, DENTAL | EFB | NAKANISHI INC. | Z800L |
Patients
| Seq | Age | Sex | Outcome | Treatment |
|---|---|---|---|---|
| 1 | Unknown | Other |